Oct. 17, 1889] 



NATURE 



607 



It being thus clearly established what are cqidvalent weights 

 of elements, the conception of equivalents may be further deve- 

 loped by exercises in acidimetry carried out by the pupils them- 

 selves. The proportions in which washing-soda and hydrogen 

 chloride interact may be determined by mixing solutions of 

 known strength until neutralization is effected ; if the solution 

 be evaporated and the chloride weighed, the results may be used 

 in calculating the composition of hydrogen chloride ; they serve, 

 in fact, as a check on the conclusions previously arrived at as 

 to the composition of washing-soda and hydrogen chloride. 

 Solutions of sulphur'C and nitric acid may be similarly neutralized, 

 and, the amounts of sulphate and nitrate formed having been 

 ascertained, the equivalents of the acids may be calcula'ed on 

 the assumption that the action is of the same kind as takes place in 

 the case of hydrogen chloride. Determinations of the strengths 

 of acids, &c. , rray then be made. In a similar manner the volu- 

 metric estimation of silver may be taught, and the percentage of 

 silver in coinage and other alloys determined. 



Such a series of quantitative exercises as the foregoing, when 

 carried put before and to a considerable extent by the pupils, 

 undoubtedly affords mental discipline of (he very highest order, 

 and is effective of good in so many ways that the value of such 

 teaching cannot be over-estimated. The failure to grasp quan- 

 titative relationships which examiners have so frequently to 

 deplore is without question largely, if not alone, due to students' 

 entire ignorance of the manner in which such relationships have 

 been determined. Moreover, the appreciation by the general 

 public of the principles on which quantitative analysis is founded 

 would undoubtedly be directly productive of good in a 

 multiplicity of cases. 



Stage VI. — Studies of the physical properties of gases in 

 comparison zvith those of Uqtiids and solids. 7 he molecular 

 and atomic theories and their application. 



A series of quantitative experiments on the effect of hrat on 

 solids, liquids, and gases should now be made, and these should 

 be followed by similar experiments on ^he effect of pressure ; the 

 similar behaviour of gases, and the di-similar behaviour of liquids 

 and solids, is thus made clear. The condensation of gases is 

 then demonstrated and explained, and also the conversion of 

 solids and liquids into gases, and the dependence of boiling- 

 point on pressure and temperature. Regnault's method of 

 determining gaseous densities is studied, and the method of 

 determining vapour densities is illustrated. The molecular 

 constitution of a gas is now discussed ; the phenomena of 

 gaseous and liquid diffusion are studied, and a brief reference is 

 made to the kinetic theory of gases ; then Avogadro's theorem 

 is expounded and applied to the determination of molecular 

 weights ; and eventually the atomic theory is explained, and the 

 manner in which atomic weights are ascertained is brought home 

 to the pupils. The use of symbols must then be taught. Finally, 

 the classification of the elements in accordance with the periodic 

 law should be explained. 



It is all-important that at kast a large proportion of the 

 experiments in each of the stages should be made by the pupils ; 

 but even if this were not done, and the lessons took the form of 

 demonstrations, much valuable instruction might still be given. 



The majority of pupils probably would not proceed to the 

 fifth and sixth stages ; but those who perforce must terminate 

 their studies without gaining any knowledge of chemical 

 philosophy should unfailingly be led to make a few simple 

 quantitative experiments : for example, to deleruiine silver 

 volumetrically, and the method of determining the composition 

 of water and chalk gas should be demonstrated in their presence : 

 and it may be added that, if only the examples in Stages I. and 

 11. and Problems I. to V. of Stage Til. were thoroughly worked 

 out, most important educational training would be given, and 

 much valuable information as •to the nature of common 

 phenomena would be gained. 



The complete course would undoubtedly take up considerable 

 time, but so does a satisfactory mathematical or classical course 

 of study, and it is absurd to suppose that useful training in science 

 is to be imparted in a few months. If instruction be given in the 

 manner suggested at all generally, it will be necessary, however, 

 to modify the present system of testing results. Pupils could 

 not be expected to pass at an early age examinations such as 

 are at present held, and awards would have to be based chiefly 

 on an inspection of the classes at work and of note-books and on 

 vivA voce questioning. But all are agreed that the present 

 system of payment on results tested by a terminal examination 



is a most unhealthy one, and that a more rational system muse 

 be substituted for it. I may suggest that if members of the staff 

 of science colleges, such as are now established in so many towns, 

 could be appo-nted 5«/«-7?>w^ /«i/<'r/^;.r, whose duty it would 

 be to advise teachers in schools and occasionally to inspect the 

 teaching in company with the permanent inspector, it would be 

 possible to secure the assistance of a body of men who are in 

 touch whh scientific progress and conversant with the improve-^ 

 ments which are being effected. A man who "once an inspector 

 is always an inspector" of necessity must get into a rut, and will 

 escape from the wholesome leavening and rousing influence 

 which is always more or less felt by those whose ofSce it is to 

 follow the march of scientific progress. 



It should also here be pointed out that the great majority of the 

 experiments and exercises described may be carried out with very 

 simple apparatus, and with slight provision in the way of special 

 laboratory accommodation. In but very few cases is there any 

 production of unplea'-ant smells or noxious fumes. It is, in fact, 

 a mistake to suppose that an elaborately fitted laboratory is in^ 

 every case essential for successful teaching : much might be done 

 in an ordinary schoolroom provided with a demonstration bench 

 for the use of the teacher, a draught closet over the fire-place, 

 a sink, a raised table for balances (raised so that the teacher 

 might see what was going on), a cupboard for apparatus, and a 

 long narrow bench provided with gas-burners at which, say, 

 twenty pupils might stand, ten a-side. At present the Science 

 and Art Department will not recognize "practical chemistry" 

 unless it be taught in a laboratory fitted up in a certain specified 

 manner, and their regulations are such as to enforce the provision- 

 of expensive laboratories in all cases where it is desired to obtain 

 the grant. If greater latitude in fittings were allowed, more 

 attention being paid to the character of the woik done and IcfS- 

 to the tools with which it is accomplished, probably much le!S 

 money would be wasted by inexperienced school authorities in 

 providing special laboratories, and there would be much grea'er 

 readiness displayed to enter on the teaching of experimental 

 science. The course which has been sketched out is one which 

 doubtless might well be modified in a variety of ways according 

 to circumstances. Thus many simple exercises in mechanics, in 

 addition to those directly mentioned, might be introduced into 

 S'age II., end the mechanical properties of common materials 

 might be somewhat fully studied at this stage in districts where 

 engineering trades are largely established, and where such 

 knowledge would be specially valuable. In like manner the 

 physical effects of heat on substsnces might be studied in 

 Stage III. instead of Stage VI. And there are other chemic.nl 

 problems and simple exercises besides those described which 

 might be substituted for some of them, or included in the 

 course. 



Probably, however, it would be found undesirable, if not 

 impossible, as a rule, to continue the teaching of chemistry 

 proper much, if at all, beyond the stage indicated in this scheme. 

 Other subjects will have a prior claim should it ever be deemed 

 essential to include in a comprehensive scheme of school education. 

 the elements of the chief physical and physiological sciences ;. 

 it certainly is of primary importance to introduce at as early a 

 period as possible the conception of energy, and to explain the 

 mechanical theory of beat, so that later on it may be possible to 

 discuss the efficiency of heat and other engines; and, until the 

 laws of the electric current are understood, the subject of chemical 

 change can never be properly considered. 



In many cases, where it is convenient or desirable to continue 

 the chemical studies, it probably will be advantageous as a rule 

 that they have reference to specific (local) requirements— (r._^. to 

 agriculture in schools in agricultural districts ; to food materials 

 and physiology in the case of girls especially, &c. But in any 

 case more consideration must be paid in the future in schools 

 where chemistry is taught to educational requirements — the 

 teaching must have reference to the requirements of the general 

 public ; and it must be remembered that the college, not the 

 school, is the place for the complete study of a subject. 



With (he object of presenting in an available form information 

 as to (he position occu]5ied by chemistry in Board and other 

 public elementary schools, which are controlled either by the 

 Education Dej:ar(ment, Whitehall, or (he Science and Art 

 Departrrent, South Kensington, the Committee now present a 

 report on the subject which has been prepared by Prof. 

 Smiihells. A consideration of this statement will show that, as- 



